USB-DUX sigma

GND is available on many pins on the HD connector
(check out the pinout)
so that you can choose the ones which are easiest to solder to.
R5 should be soldered
close to the D connector (e.g. inside of the backshell) which acts as a termination
and prevents oscillations.
To be able to measure negative temperatures connect a 100K resistor between pins 16 and 31 (-5V).

Software

comediecordis recommended to record data for offline processing,
for example in OCTAVE or MATLAB.
It saves the data in a OCTAVE/MATLAB compatible format and you can watch the data while it's being
recorded.

comedi 2 python
allows realtime processing of your temperature readings in python. You can plot your data with a few commands or
send out control signals via the D/A port (for example to a heater) to establish closed loop realtime control.